ACES SYSTEMS Cobra II, Руководство пользователя

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Gen II
User Manual
16-3 – Monitor Spectrum Chapter 16 Revision 2.10, Apr 2020
frequencies selected in paragraphs 16.1.1.3 through 16.1.1.4 and the Res. Lines entry
selected in paragraph 16.1.1.5. This can be helpful if you are trying to separate one single
peak into two very close peaks. The value displayed will be the frequency interval
between each pair of lines on the final spectral display.
16.1.1.7. Use the [

] key to move to the “Average Type” field. Select the average type by scrolling
through the selections in the field using the [

] key until your selection is displayed.
There are three available options: “Exp”, “Normal”, and “Peak Hold”. If you select
“Exp” the screen will constantly update both the amplitude and frequency. The screen
will have a dynamic appearance and change as the input condition changes. The analyzer
will continue to collect data until stopped by pressing [OK]. If you select “Normal” the
analyzer will acquire only the total number of blocks specified in paragraph 16.1.1.8
below, then automatically stop data acquisition, average the collected blocks and plot
them on screen. If you select “Peak Hold” the analyzer will plot and hold the highest
amplitude received on screen. These values will not decrease once plotted, but will
increase if amplitude of higher value is acquired. The analyzer will continue to collect
data until stopped by pressing [OK]. Consult the appropriate equipment maintenance
manual for specific requirements of a vibration survey or for analysis guidelines.
16.1.1.8. Use the [

] key to move to the “Blocks in Avg.” field. Enter the number of data blocks
you wish to be used in the calculations. This is the total number of samples taken, and
then averaged before being plotted on the screen. The default is four. The valid range is
0 to 999. Remember that higher numbers of averaging, while providing more reliable
data, also require more time. The default value of 4 is sufficient for most applications.
NOTE
Sensor Channels C & D are only available on the Viper II
16.1.1.9. Use the [

] key to move to the “Units” column of the Channel A row. This field
determines the engineering units in which the amplitude, or “Y” axis, of the spectra will
be displayed. A selection of “None” in the field indicates there will be no input to the
Channel adjacent to the field where the word “None” appears. Consult the appropriate
equipment maintenance manual for specific requirements of a vibration survey or for
analysis guidelines. Use the [

] or [

] keys to scroll through the selections in this field.
The available selections are: G’s (equivalent gravities), IPS (Inches Per Second), mm/sec
(millimeters per second), cm/sec (centimeters per second), Mils (1/1000th of an inch),
Microns (1/1000000th of a meter), ubars (Millibars), Pascals, Volts, m/s/s (meters per
second per second), cm/s/s (centimeters per second per second, dB (decibels), Special
and None.
NOTE
Selecting mils or microns in this block will not allow you to select any accelerometer input in